Update 8.30am Warrnambool is shivering through its coldest day of the year so far. Temperatures have continued to drop as the sun rises, with Warrnambool sitting at -0.6 degrees at 8am, as well as Mortlake at -0.8, Westmere at -1.1 and Casterton at negative one. Earlier Thursday has kicked off to a cold start with temperatures dropping to below zero. The temperature at 7am was -1.1 degrees in Casterton, -0.6 in Hamilton, -0.3 in Mortlake and -0.2 in Westmere. Warrnambool was 0.5 degrees and it felt like -2.3. Cape Nelson received the highest total rainfall with 16.2mm since 9am Wednesday, followed by 8.2mm at Casterton and 6.2mm at Dartmoor. Bureau of Meteorology senior forecaster Dean Stewart said the south-west region could expect some fog areas in the morning but dry conditions for the rest of the day with a cool top of 12 degrees. Overnight temperatures are expected to fall to around one degrees.